Aquatic Biology Data Summary

Below are six charts that summarize the data collected over the past few years: turbidity, dissolved oxygen, temperature, pH and macroinvertebrates observed.

Turbidity. Measures how much dirt and other particles are floating in the water. It is used as an indicator of water quality. The higher the NTU (Nephelometric Turbidity Units) value, the cloudier the water is. A lower turbidity value indicates clearer water.

Greater turbidity may decrease an animals’ ability to remove oxygen from the water through gills, reduce visibility for predators and prey, reduce light for plants, decrease quality of drinking water, fill transportation routes with sediment, and impact recreation activities.

Wetlands play an important role in reducing the amount of sediment that runs into creeks, lakes, etc.

Dissolved Oxygen (DO). The amount of oxygen dissolved in water that is available for organisms to use for respiration or breathing. Clearer water — e.g. low turbidity — has more dissolved oxygen.

Temperature. Colder water can hold more dissolved oxygen. Warmer water becomes more easily saturated with gas and so can hold less oxygen.

pH. How acidic or basic (alkaline) the water is using a scale of 0 to 14. Low numbers are acidic, high numbers are basic/alkaline, and 7 is neutral.

Fresh water range is pH 6 to 9. pH increases (becomes more basic) with effluents, photosynthesis and aeration. pH decreases (becomes more acidic) with increased rainfall and decomposition of plants.

Macroinvertebrates. Aquatic animals without backbones that are visible to the naked eye, and typically found in and around water. Juveniles (e.g. nymphs and larva) are usually found in the water, among rocks, litter, and sediments. Adults are usually found on the water surface, in the air, and around plants near the water.